The present invention relates to a single-operational amplifier resonating device, and more particularly to a low cost resonator with large tuning range.
In the field of data transmission system, an integrator or a resonator is an important circuit element. One purpose of the resonator is to realize a high quality-factor (Q) band-pass response for some circuit blocks in the system. Therefore, the resonator can be applied in a filter or a high resolution delta-sigma modulator. Conventionally, a resonator comprises two integrators connected in a way of negative feedback configuration, wherein one integrator comprises an operational amplifier. However, the conventional resonator is no longer suitable for the modern data transmission system because the two operational amplifiers in the resonator may occupy a large size area. Moreover, the modern data transmission system may require a wide tuning range resonator in order to operate under a wideband environment. Therefore, how to provide a low cost and wide tuning range resonator is an urgent problem in this field.